This invention is related generally to electrical connectors for medical use and, more particularly, to medical connectors for multi-contact medical electrodes for use in facilitating surgical procedures.
A variety of multi-contact medical electrodes, including depth electrodes, subdural strip electrodes and grid electrodes, are placed in the human body for various purposes, such as brain-mapping in epilepsy treatment. The plurality of wires necessarily extending from such electrodes typically lead to a plural-contact tail, which is a linear dielectric member with a linear array of sleeve-like contacts spaced therealong. Such plural-contact tails of multi-contact medical electrodes have been electrically joined to other equipment, such as monitoring equipment, by means of connectors designed specifically to accommodate such tails.
Many different connectors have been developed to facilitate such plural-contact connection. Examples of such prior plural-contact medical connectors are those disclosed in the following United States patents: U.S. Pat. No. 4,850,359 (Putz), U.S. Pat. No. 4,869,255 (Putz), U.S. Pat. No. 4,744,371 (Harris), U.S. Pat. No. 5,560,358 (Arnold et al.), U.S. Pat. No. 5,902,236 (Iversen), U.S. Pat. No. 4,516,820 (Kuzma), U.S. Pat. No. 4,712,557 (Harris), U.S. Pat. No. 4,461,304 (Kuperstein), U.S. Pat. No. 4,379,462 (Borkan et al.), U.S. Pat. No. 4,633,889 (Talalla et al.) and U.S. Pat. No. 4,676,258 (Inokuchi et al.).
Certain medical connectors of the prior art have a number of shortcomings and problems. Some prior connectors generally require a number of manual steps to operate, even for the final step of causing simultaneous electrical connection of the plural contacts. One-handed connection and disconnection may not be readily possible. Some prior devices require multiple parts which add to their complexity of operation.
Simplicity in structure and operation is particularly important considering that connection and disconnection typically occurs in a surgical setting, in which a surgeon or other doctor must be giving great attention to many other factors. Complexity in parts and operational procedures is a significant shortcoming, one which is important by medical personnel involved.
Maintaining reliable and constant connection throughout the period of use is another important consideration. Connectors which tend to provide electrical contact which is variable, depending on factors such as the degree of tightening, can be problematic. Still another shortcoming of certain prior art connectors is the lack of a definitive indication that electrical connection has been accomplished and put into effect.
Another concern with certain medical connectors for multi-contact electrodes, particularly in situations involving seizure disorders, is that devices essential to proper electrical connections can too easily be destroyed by inadvertent motions. More specifically, the plural-contact tails of multi-contact electrodes can break, or their plural contacts become dislodged, when forceful inadvertent yanking or pulling motions occur, as can occur during seizures. This is not a simple problem, because destruction of a plural-contact tail may make it difficult or impossible for a physician or technician to ascertain the proper association of contact leads with in-body contacts, and this makes further reliable use difficult or impossible for the in-body electrode associated with the destroyed plural-contact tail.
In summary, there remains a number of problems and shortcomings in prior connectors for use with multi-contact medical electrodes.
It is an object of this invention to provide an improved connector for multi-contact medical electrodes overcoming some of the problems and shortcomings of the prior art.
Another object of this invention is to provide an improved multi-contact medical connector which is simple in structure and operation in order to facilitate operations, including during surgery.
Another object is to provide an improved multi-contact medical connector requiring fewer manual steps to accomplish electrical connection.
Another object is to provide an improved multi-contact medical connector allowing one-handed operation in the final connection and disconnection steps.
Another object is to provide an improved multi-contact medical connector which gives highly reliable electrical connections with minimal effort.
Another object is to provide an improved multi-contact medical connector which gives a definitive indication of the completion of electrical connection.
Still another object of the invention is to provide an improved multi-contact medical connection which is less susceptible to destruction of key connection parts due to inadvertent yanking, as can occur by virtue of seizure disorders.
These and other objects of the invention will be apparent from the following descriptions and from the drawings.
This invention is an improved electrical connector for in-body multi-contact medical electrodes having linear-array plural-contact tails. The electrical connector is of the type having a tail-receiving member and means movable with respect thereto for quick connection and disconnection of all contacts.
The improved multi-contact medical connector of this invention includes first and second elongate members which are pivotable with respect to one another about a pivot axis extending along their lengths. The first elongate member has a first face and an array of electrical conductors positioned therealong in an array which matches the spacing of the plural contacts of the plural-contact tail of the medical electrode with which the connector is used. The second elongate member extends along the first elongate member and has a tail-receiving void, a second face which is parallel to the void, and access openings along the second face to expose the plural tail contacts at the second face. The second elongate member is pivotable between open and closed positions with respect to the first elongate member. The pivoting is about an axis which extends along the common lengths of the elongate members. The closed position serves to place the plural contacts of a plural-contact medical electrode tail into engagement with the electrical conductors.
In highly preferred embodiments, the second face is movable upon pivoting between the open position at which the second face is away from the first face and the closed position at which the second face is juxtaposed to the first face, and the electrical conductors are spring-loaded ball plungers along the first face which are biased toward the second face to facilitate electrical engagement with the plural contacts of the tail. The first elongate member preferably defines cylindrical wells (or xe2x80x9cchannelsxe2x80x9d) along the first face which receive and hold the spring-loaded ball plungers. Such channels are preferably perpendicular to the first face. The distal ends of the ball plungers are held near the first face in positions for biased engagement against the contacts of the multi-contact tail when the first and second faces are in juxtaposition to one another.
In certain preferred embodiments, the second elongate member has proximal and distal ends and the void extends from an opening at the proximal end to a stop near the distal end, and the first elongate member includes a pair of opposed inwardly-facing endwalls between which the second elongate member extends in nested fashion with its ends adjacent to the endwalls. The proximal end of the second elongate member is that end into which the multi-contact medical electrode tail is inserted, and the distal end is the opposite end.
In certain of such preferred embodiments, one of the endwalls forms a cutaway portion through which the electrode tail passes, thereby allowing pivoting movement of the second elongate member without interference with the electrode tail. Preferably, the pivot axis extends through both endwalls and both ends and at least one pivot pin extends along a portion of the pivot axis between at least one of the endwalls and the end adjacent thereto. Two pivot pins along such axis are preferably usedxe2x80x94one spanning between combination of endwall and end.
In preferred embodiments, the first and second elongate members have first and second stop surfaces, respectively, which abut one another to define the closed position, and at the closed position the second elongate member positions the electrode tail such that the spring-loaded ball plungers are just beyond-center (overcenter) with respect to the plural contacts of the tail. This configuration serves to provide reliable electrical contact and also helps to keep the connector in the closed position.
In certain preferred embodiments, the second elongate member includes a grip flange which serves to facilitate pivoting of the second elongate member from the closed to the open position. Such grip flange extends away from the pivot axis and provides a thumb-grip surface.
In certain highly preferred embodiments, the ball plungers protrude beyond the first face toward the second elongate member, and the access openings on the second face are designed to facilitate the closing action during which the plural contacts of the medical electrode tail are brought into engagement with the ball plungers. More specifically, the second face has a lead edge which is adjacent to the second stop surface when the second elongate member is in the closed position, and the access openings on the second face extend laterally to the lead edge such that the second elongate member has lateral openings receiving the ball plungers as the second elongate member is pivoted to the closed position.
The medical connector of this invention has significant advantages over connectors of the prior art. The connector is compact, at least in part from the fact that the orientation of the pivot axis, which is along the length of the first and second elongate members, minimizes the space in which opening and closing movement occurs. The medical connector of this invention is also very easy to use in that it can be opened and closed with one hand. The connector also provides excellent electrical connections and provides definite open and closed positions to facilitate operation and understanding.
The invention includes the medical connector as described above, and also includes the combination of such a connector with the linear-array plural-contact tails of a multi-contact medical electrode. In highly preferred embodiments, the plural contacts of the plural-contact tail are annular sleeves having necked-in (e.g., crimped) ends. This configuration of plural-contact tail with the medical connector of this invention with its spring-loaded ball plungers allows quick withdrawal of the plural-contact tail without destruction of the plural-contact tail. A sudden pull allows the plural-contact tail to pull out from the connector even while the connector is in its closed position. This is brought about by the combination of spring-loaded ball plungers and the necked-in annular-sleeve contacts. The contacts will ride right over the line of ball plungers without causing destruction of the plural-contact tail.
This advantage is significant in that it minimizes or prevents the problems which can occur if a patient""s seizure causes violent jerking and yanking movements during e.g., a brain-mapping session. Such activity can result in the need for an expensive and time-consuming reorganization and reassembly of electrical components in order to allow resumption of the intended medical activity.